Structural characterization of an all-aminosugar-containing capsular polysaccharide from Colwellia psychrerythraea 34H

Abstract

Corresponding author: corsaro@unina.it. Colwellia psychrerythraea strain 34H, a Gram-negative bacterium isolated from Arctic marine sediments, is considered a model to study the adaptation to cold environments. Recently, we demonstrated that C. psychrerythraea 34H produces two different extracellular polysaccharides, a capsular polysaccharide and a medium released polysaccharide, which confer cryoprotection to the bacterium. In this study, we report the structure of an additional capsular polysaccharide produced by Colwellia grown at a different temperature. The structure was determined using chemical methods, and one-and two-dimensional NMR spectroscopy. The results showed a trisaccharide repeating unit made up of only amino-sugar residues: N-acetyl-galactosamine, 2,4-diacetamido-2,4,6-trideoxy-glucose (bacillosamine), and 2-acetamido-2-deoxyglucuronic acid with the following structure: Europe PMC Funders GroupThe 3D model, generated in accordance with 1 H, 1 H-NOE NMR correlations and consisting of ten repeating units, shows a helical structure. In contrast with the other extracellular polysaccharides produced from Colwellia at 4 °C, this molecule displays only a low ice recrystallization inhibition activity.

Polysaccharide hydrolysis in the presence of oil and dispersants: Insights into potential degradation pathways of exopolymeric substances (EPS) from oil-degrading bacteria

“…Analysis of EPS produced by Marinobacter isolates revealed high levels of carbohydrates with a broad range of structural monosaccharides (Caruso et al, 2019), including xylose (Bhaskar et al, 2005). Members of the genus Colwellia isolated from cold waters and sediments produced cryoprotectant EPS (Marx et al, 2009) as well as EPS enriched in deoxysugarcontaining polysaccharides (Casillo et al, 2017). The latter are major components of particulate EPS and TEP (Mopper et al, 1995;Zhou et al, 1998), which also formed in our WAF amendments (Table 4).…”

Exopolysaccharides from Marine and Marine Extremophilic Bacteria: Structures, Properties, Ecological Roles and Applications

“…When Colwellia is grown at 8 °C, it is able to produce a third polysaccharide, which is not endowed with antifreeze activity. This is a polymer containing amino sugars and aminouronic acids and it is not decorated by amino acids ( Figure 4 g, Table 2 ) [ 80 ]. It has been hypothesized that the lack of these substituents does not settle the equilibrium between the hydrophobic and the hydrophilic regions necessary to the establishment of the IRI activity.…”

Plant Dynamic Metabolic Response to Bacteriophage Treatment After Xanthomonas campestris pv. campestris Infection

“…Glycosyl analysis of Xcc cells in biofilm (Figure 3A) revealed the presence of rhamnose (Rha), mannose (Man), glucose (Glc), and traces of galactosamine (GalN) and glucosamine (GlcN), all main components of exopolysaccharides (EPS; Casillo et al, 2017a). Phage analysis (Figure 3B) indicated the presence of Glc, galactose (Gal) and, at a lower concentration, Man, whereas the latter two are uncompetitive inhibitors of bacterial biofilm stability.…”